Prostaglandin synthesis in human placenta and fetal membranes: partial inhibition by rat and human alpha-fetoproteins.

The conversion of exogenous arachidonic acid into prostaglandin E2 (PGE2) was studied in human placenta and fetal membranes microsomes Rat and human alpha-fetoproteins (AFPs) at 170 micrograms/ml in the incubation medium, a concentration that does not exceed the physiological concentration observed in rat and human body fluids during pregnancy, decreased by 75% and 90% respectively the amount of PGE2 synthesized. The regulation of PGs synthesis by AFPs can shed a new light on different aspects of the numerous physiological actions of AFPs previously described such as ovarian regulation of immunosuppressive activity.